A dance mocking the well-known Tango. Often danced to Tango music, this dance is to be danced with a serious face but a jovial spirit. The point is to be absolutely ridiculous, and has even become a competition to see who, on the dance floor, can pull off the most humorous Jango.

Unknown whether this originated as the Joke Tango, Jive Tango, or named for it's inventor, James Tango.

"Oh look! They are doing the Jango!"

"Did you see James and Alethea doing the Jango? They were fantastic and hilarious!"

Used as an insult it originates from the bounty hunter Jango Fett in the Star Wars Movies.
Meaning someone who is of the Dark Side, with more literal meanings being 'dick', 'fool', idiot', 'jerk' and so on.